... The new U.S. report, as well as a United Nations report issued in October, instead aim at frightening the public—exactly the approach that so manifestly has failed to move the needle for 35 years. Maybe it’s because voters are skeptical of doom-mongering. Maybe they have grown fatalistic about climate change. Or maybe, reflecting the folly of climate campaigners, they’ve gotten a message that acting on greenhouse gases requires giving up prosperity. Reporting Sunday on the French fuel-tax demonstrations, the New York Times noted: “Many in the crowd said that they did not disdain the government’s environmental goals, but that...